The transatlantic slave trade lay at the centre of a complex global commercial system. It was also the cause of an occasion for international rivalries and tensions on three continents. Europeans fought each other for a share of the trade to and from Africa. They clashed over possessions in the Americas that required slave labour. And they even disputed each other's presence on the high seas. That slaves and the slave trade lay at the heart of such friction, over many centuries, is itself proof of the value Europeans attached to slavery itself.
From gold and spices to slaves
Europeans had initially encountered the peoples and commodities of sub-Saharan Africa via ancient overland routes across the Sahara and along the Nile. Direct contact took place when, in the 15th and 16th centuries, traders and adventurers cautiously sailed along the African coast, which gave them access to West Africa and thence to trading routes deep into the African interior.
Portuguese and Spanish seafarers shipped enslaved African people to Spain and Portugal and to their islands in the Atlantic, but slaves were only a small part of what interested these adventurous traders: gold, spices, dyes, and timbers, ivory – a host of African commodities – were far more attractive.
But all those were pushed aside, after 1600, by the lucrative development of plantations in the America. Henceforth, humans, not inanimate commodities, were the greatest commercial attraction for European traders along a vast stretch of African coastline, from Senegambia to Angola.
The African coast
The Spaniards and Portuguese pioneered the slave trade. Like those who followed, they depended for supplies of enslaved people (along with other items) on trading contacts along the African coast. Sometimes they traded with powerful African kingdoms – for instance, Kongo – and sometimes with African middlemen who dominated trade routes into the interior. Although Europeans began to build 'slave dungeons’ and forts along the slave coast – notably along the ' Gold Coast', modern-day Ghana – they rarely had more than a tentative toe-hold on the African shore.
Slave trading varied greatly from place to place, much depending on local geography. Sometimes it was carried out from settled communities, sometimes from forts and established bases. Often Europeans traded from their ships riding offshore.
In 1493, the initial division of slave trading regions between Spain and Portugal had been made by Pope Alexander VI. In the Treaty of Tordesillas, Spain was given all of the Americas, while Portugal had Africa and India. Then, in a further treaty a year later, Portugal was given Brazil. However, the arrangements in Africa were eventually contested by the newly emergent European maritime powers – by, in turn, the Dutch, the English and the French.
The scramble to join the trade
Spain didn't engage in the slave trade directly but was supplied with Africans by various countries via a series of asientos (contracts). However, other maritime nations wanted their own slave trade. The English, for example, established a joint-stock enterprise, the Royal African Company, but this monopoly failed to provide planters with what they wanted and simply gave way under the growing colonial demand for more forced African labour. When a freer British slave trade was finally established – after protracted political and commercial argument – it ushered in an era of massive expansion. Enslaved Africans crossed the Atlantic in huge and increasing numbers. By the peak years of the 18th century, the British were shipping 40,000 people a year.
European traders scrambled to join in the slave trading business. Monarchs and princes, powerful merchants and landowners, even small craftsmen and modest property owners invested in slave ships. They all hoped it would yield the fabled wealth that quickly came to be attached to transatlantic slavery. In fact, the profits derived from slave voyages were often more modest than we imagine, but the prospects of great profit lured people of all sorts and conditions to invest in the trade in African humanity.
Goods to Africa
Europeans soon came to view slavery as simply another form of oceanic trade. In return for the growing numbers of African captives loaded on to their slave ships, they had to offer tangible items to the African merchants. Each side – usually European and African, and traders gradually learned what they needed to supply to buy slaves or were given specific instructions.
Arms and metal goods, textiles and luxuries, metal bars – all were carefully placed in the holds of outbound ships in the hope of exchanging them for enslaved Africans. Of course, in the process, Europeans acquired more than the slaves, purchasing other African commodities, notably precious items – gold, ivory – and the exotic spices of the region.
Trading was often accompanied by violence, but the initial European snatching and grabbing of Africans – a form of piracy against them – quickly gave way to conventional barter and trade. Both sides knew what the other wanted, and both tried to trade to their own advantage.
A regulated business
The slave trade became a highly regulated business, as each slaving nation sought to license and control its own part of it. The trade received formal state backing from monarchs and from legislatures, while attracting little criticism from religious bodies. And those states sought to enhance their own slaving strength not merely by force of arms, but by diplomacy and treaties. Like the Spanish and Portuguese, they agreed to trade in specific regions and signed treaties to provide Africans to other colonies, allowing their opponents to trade elsewhere.
The British slave trade was carefully regulated from its early days. Even the first efforts of privateers – notably Sir John Hawkins– were subject to royal approval. In the 18th century, royal backing (it was, after all, the Royal African Company) gave way to full-blown parliamentary support. Indeed Parliament spent as much time discussing (and legislating for) the expansion and regulation of the slave trade as it was to spend on abolition a century later, passing dozens of Acts to fine-tune the trade.
Similarly, slavery in the colonies was regulated by colonial laws approved in London. What this means is that the trade in Africans and the use of colonial slavery were not merely haphazard offshoots of economic growth: they were the subject of considered political and legal attention in London, as well as in other European capitals.
In addition, the trade was made possible by the development of modern financial systems. Global trade on such a vast geographic scale involved enormous time lags. Slave ships were away from their home ports for 12–18 months at a time, and sugar and tobacco were sold in Europe many months after being harvested by slaves. As a result, ship owners and planters were always in need of credit – especially for the purchase of Africans – and so evolved a complex international system of flows of cash and commodities and bills of credit. This made possible the buying of African slaves and the produce they cultivated and harvested. Equally complex systems of insurance developed to cover the risks and dangers of oceanic trade.
Britain's gains from the slave trade
We know of about 40,000 slave voyages over the history of the slave trade, and the image of the slave ships remains perhaps the best-remembered feature of the trade itself. Some 12 million Africans were loaded on to those vessels, which ranged from small craft weighing only a few tons to huge ships of 500 tons. The experience of the voyages traumatised the Africans who survived them, and memories of the crossing entered the folklore of slave communities across the Americas.
The ships operated from most of Europe's major ports, though by the late 18th century, quite a few were based in the slave ports of the Americas, notably Newport, Rhode Island and Rio de Janeiro in Brazil. In Britain, the trade was, by turns, dominated by London, Bristol and Liverpool.
The physical and social development of the last two cities was clearly tied up with the slave trade and with the buoyant commerce needed to build, fit out and fill slave ships. The trade gave employment not only to huge numbers of sailors, but it spawned jobs in a host of local industries – in the port itself and also far into the hinterland.
Despite the prominence of Liverpool, Bristol and London, and many other British ports profited from some involvement in the slave trade – some, like Glasgow, through the importation of slave produce, others, like Whitehaven in Cumbria and Lancaster, from direct trafficking in human lives. Between them, these two ports accounted for more than 43,000 enslaved Africans being taken out of Africa.
Textiles from Yorkshire and Lancashire, salt from Cheshire, pottery from Staffordshire, metal goods (chains, fetters, manacles … and guns) from the Midlands – all were transported along the canals to Liverpool to be loaded on to the slave ships bound for Africa and the Americas. Ireland provided enormous amounts of food to feed crews and slaves and to be shipped to the American plantations. The slave ships were weighed down by materials and produce from all corners of the British Isles, and much of it was consumed by Africans or exchanged for Africans on the African coast.
While the slave ships provided the plantations with the African labour required for tropical toil, the colonists needed more than that and so were also dependent on the transatlantic shipping routes for their survival. They required a constant supply of imports in addition to enslaved Africans – equipment, seeds, plants, animals, metal goods, factory equipment, food and clothing for the slaves, timber for construction.
In return, extraordinary volumes of slave-grown produce were shipped eastwards: sugar and rum from the Caribbean and Brazil; tobacco from Virginia and, later, from Cuba; rice from the Carolinas; coffee from Jamaica and Brazil; and, in the 19th century, enormous quantities of cotton from the southern United States to feed the industries of Britain. After delivering their African cargoes, the slave ships transported some of this slave-grown produce back to Europe. However, many more non-slave ships were required to transport all that the plantations produced.
Although it is tempting to think of the slave trade as a 'triangular' system, it was much more complex than that label suggests. The term is Eurocentric in its view as it begins and ends with Europe. There were, for example, slave ships that traded exclusively between Africa and South or North America. Other ships sailed back and forth between Europe and Africa, and still others from Europe to the Americas and then back with produce. There was, in fact, a complex mesh of shipping routes in the Atlantic, ferrying people and goods back and forth between all the major points of the slaving compass.
Inevitably, however, the slave trade caused friction and conflict. European rivalries in the 17th and 18th centuries were played out in all the corners of globe. When at war, as they often were, slave trading nations did their best to grab their opponents' ships and fought each other for access to, or control over, the slave trading sites, the transatlantic trading routes and the much-prized slave colonies. They did this not merely because of the prevailing belief in empire and colonisation, but because slavery yielded such material bounty to the winners, as exemplified by the castles (slave dungeons) on the Gold Coast, notably St Jorge's at Elmina.
The slave trade changed markedly over time, reflecting the changes in political and military power among the nations involved in it. The initially dominant Portuguese were replaced by the Dutch in the late 16th century. They, in their turn were usurped by the British and French from the 17th century. These two struggled for supremacy in the 18th century, not merely in the Atlantic but all over the world, from India to North America and the Caribbean. Although Britain – and especially Liverpool – dominated the slave trade by mid-century, the ports of Nantes and Bordeaux and, above all, the expansive colony of St Domingue – what would become Haiti – threatened to push the British aside. That threat ended with the outbreak of the French Revolution in 1789, the Haitian slave revolution of 1791 and the subsequent collapse of French power in the enslaved Caribbean.
The 'illicit' slave trade
After the British abolished their slave trade in 1807, 'illicit' slave traders from Spain, Portugal and Brazil, working mainly in the south Atlantic, were harried and pursued by the British naval factions on both sides of the Atlantic. Nevertheless, there was a notably British involvement in the continuing slave trade. We now know that, despite the British and American anti-slavery patrols and British diplomatic pressure to prevent slave trading in the Atlantic, another 3 million Africans were transported across to the Americas (mainly to Cuba and Brazil) between 1807 and 1860. Increasingly, it was a trade in children, drawn mainly from central Africa. Thereafter the transatlantic trade died out.
After 1800 in the United States, slave trading was internal, not oceanic, with slaves being moved westwards from the old slave states to the new cotton frontier.
The consequences of slavery and the slave trade
Arguments continue about the profitability of the transatlantic slave trade, but what remain indisputable are the remarkable economic and social consequences generated by it. It was responsible for the enslavement of millions of Africans: the 12 million loaded on to the ships were only a percentage of those enslaved initially in Africa. It made possible the profitable cultivation of key areas of the Americas. It spawned expansive industry in Europe and the Americas, and it generated a complex financial system – borrowing, lending and insuring – which profited the major merchants, lending houses and banks of Europe and the Americas.
It also generated a remarkable transformation in Europeans' way of life. They now consumed new crops – tobacco, sugar, rice – grown by Africans forcibly shipped across the Atlantic. They also mixed slave-grown sugar with tea imported from China or coffee from the Horn of Africa or Dutch Indonesia, drinking it from cups made in China. Here was a truly global trade made possible by the transatlantic slave trade.
Yet in all discussion about profitable commerce, we need to recognise that not only did the slave trade create desperate unhappiness and despair in millions of people, it also impoverished great swathes of Africa.
We know who benefited from the slave trade, not least because they left behind ample testimony to their successes: plantation great houses, merchant's homes, major banks, rural retreats - all those and more provide testimony to the prosperity yielded by the slave trade. Less frequently noted, however, is the plight of underdeveloped African nations, and the millions of African descendants, scattered across the Americas by this slave system, who had little to show for their slave origins but their poverty.
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